山西省不同品种谷子淀粉理化性质的比较

Comparison of the physicochemical properties of different varieties of millet starch in Shanxi province

以山西省13种不同谷子品种作为供试材料,采用酶法制备淀粉,对其溶解度、膨胀度、透光率、冻融稳定性、凝沉性、热特性及结晶结构进行研究,比较其差异性。结果表明：13种谷子淀粉的溶解度及膨胀度范围分别为10.79%-19.11%,25.11%-42.91%,其中2-T9膨胀度最大,2-T3的溶解度最大,品种之间存在显著性差异;透光率为6.278%-19.39%,析水率为7.08%-60.73%,黄谷的透光率和析水率都是最高;凝沉性试验同样表明黄谷的稳定性显著优于其他品种;采用差示扫描量热仪（DSC）测定谷子淀粉的热特性,糊化起始温度、峰值温度、最终温度和相变热焓分别为52.78-70.95℃,71.12-79.26℃,80.42-88.48℃,9.83-11.87J/g,这些特性品种间差异显著;X-射线衍射分析表明13种谷子淀粉的结晶结构属于A型。

13 kinds of millet in Shanxi province were selected to prepare starch by enzymic method,and the solubility, swella- bility, light transmittance, freeze-thaw stability, retrogradation properties, thermal properties and crystalline texture were studied and compared. The results showed that： solubility varied between 10. 97% and 19. 11%, while swellability varied between 25.11% and 42.91%;2-T9 millet starch showed the highest solubility among the 13 kinds,while 2-T3 millet starch had the highest swellability,there was a significant difference between the varieties; the light transmittance and syneresis rate were in the range of 6. 278 %- 19.39% and 7.08%- 60.73%, respectively. The transmittance and syneresis rate were the highest in Huang Gu, and it also had lower retrogradation speed than other millet starchs. The differential scanning calorimeter（DSC）analysis showed that the onset temperature （To） of all millet cultivars varied from 52.78 ℃ to 70.95 ℃, peak temperature（Tp ） var- ied from 71.12℃ to 79.26℃, temperature ranged from 80.42 to 88.48℃ and enthalpy of gelatinization ranged from 9. 83 to 11.87 J/g,respectively. The millets showed an obvious difference in the physicochemical properties. X-ray diffraction （X-RD） studies showed that all millet starches were A type.